The broad objective of this research program is a better understanding of drug metabolism. Earlier work from this laboratory, particularly on barbiturates, established the patterns of biological oxidation of alkyl chains. The present application is focused on the epoxidation of the allyl group and a newly discovered enzyme, epoxide hydrolase, which converts ethylene oxides to glycols. The role of the epoxide in the metabolism of secobarbital in man and laboratory animals will be explored. Work will also be directed toward identification of the metabolites of allylisopropylacetamide that possess porphyrinogenic activity. Other facets of this research involve the metabolic fate of pentylenetetrazol and the localization of reserpine in monoamine storage granules in the brain.